Dyestuffs of the triphenyl methane series



. water,

Patented Mar. 27, 1928.-

UNITED STATES PATENT OFFICE.

OTTMAR COBPOBATIONQ OF NEW YORK, N. Y., A CORPORATION OE DELAWARE.

DYESTUFFS OF THE TBIPHENYL EETHANE SERIES.

No Drawing. Application filed April 26, 1927, Serial No. 186,830, and inGermany May 10, 1926.

My present invention relates to new dyestufis of the triphenyl methaneseries.

I have found that by reacting with one molecule of a4-benzylamino-benzaldeh 'de-' 3-sulfonic, acid upon two molecules of anaromatic-ortho-hydroxy carboxylic acid and subse uent oxidation thereare obtained new yestufis which probably have the general formulawherein R and-R are residues of aromaticortho-hydroxy-carboxylic acids.They are in a dry state reddish powders, soluble in water, soluble incaustic soda solution with a deep red color. They dye wool from an acidbath in weak reddish shades which are changed by afterchroming .tobright red to violet-red shades of good fastness to light, to fullingand potting.

The following example will illustrate my invention, the parts being byweight:

Exemplar-29 parts of' 4-benzyla1ninobenzaldehyde-3-sulfonic acid and 30parts of ortho-cresotinic acid are dissolved in 300 parts 90%strength'and stirred at a temperature of advantageously 3035 until the;aldehyde has disappeared. Then 15 parts of sodium nitrite are slowlyadded. The re-,-

action mixture is poured over ice, the dyestuif separates and isfiltered; In a dry state it is a red powder, difiicultly soluble insoluble in caustic soda solution with a deep red color. v It correspondsprobably to the formula v 00011 on a -QH:

som Q-cm oon b It dyes yvool from an acid bath weak redof concentratedsulfuric acid of aboutv which may be obtained by In the above exampleone can use instead of ortho-cresotinic acid other aromaticortho-hydroxy-carbox lic acid compounds as for instance salicy ic acidor a-hydroxynaphthoic acid. s

I claim:

1. New dyestufi's corresponding probably to the general formula KMH tothe formula COOH 0H Y 86H Q con i;

which is in a dry state ared' powder, soluble in caustic soda solutionwith a dee red color and dyeing wool from an acid ath weak reddishshades which b afterchroming are changed -to an intense y purple red,and reacting with one molecule of 4-benzylamino-benzaldehyde-3- sulfonicacid upon two molecules of orthocresotinic acid and subsequentoxidation.

In testimony whereof, I afiix my signature.

oTTMAR WAHL.

